Recently, a new commercially available instrument (TearLab®, OcuSens Inc, San Diego, USA) for the assessment of tear film osmolarity has been introduced. This instrument allows for the easy and non-invasive determination of tear film osmolarity. Unfortunately, no data about reproducibility are yet available. Consequently, the current study sets out to investigate the short time reproducibility of tear film osmolarity measurements using the TearLab® instrument.